A car navigation apparatus has been known in the past, which deals with commands originating from a remote controller. A car navigation apparatus is coming to practical use, which has a touch panel placed on a display panel to issue commands in the touch panel as well as in the remote controller. Thus car navigation apparatus has to meet two technical requirements toward practice use.
Firstly, a car navigation apparatus needs a system that distinguishes touch panel commands and remote controller commands to deal with each commands.
Secondly, a car navigation apparatus, which has a conventional remote control interface, newly needs an interface differing from the remote control interface to connect a touch screen display to a main unit thereof. The touch screen display has a display device and a touch panel. The touch panel is placed on the display device. The different interface is put between the main unit and the display device and deals with commands from the touch panel.
However, the second requirement brings increase of interface. This increase brings high cost, and complication of connection.
There are two documents that disclose usage of a touch panel. Document 1 (Published Japanese patent application H02-219083) discloses technologies for turning off software keys (GUI) used for a touch panel placed on a display panel upon leaving the touch panel not operated during a predetermined time. Document 2 (Published Japanese patent application 2005-128791) discloses technologies for switching from a current screen to other screen for remote control upon receiving commands from a remote controller during display of software keys.
However, the disclosed technologies have no difference from the car navigation apparatus that is coming to practical use, in the point of requiring an interface differing from the remote control interface.
The disclosed technologies do not enable a car navigation apparatus to switch automatically a remote controller command processing and a touch panel command processing. In other words, a screen is not switched until a user purposefully operates something or operates nothing.
According to Document 1, a user needs waiting with operating nothing during the predetermined time. According to Document 2, a user has to operate a remote controller only to switch from a current screen to a control screen.